The present invention relates to a termiticide and method for the control of termites.
There are many hundreds of commercially available termiticide chemicals and compositions. Many compositions are in liquid form which must be sprayed onto or about a termite nest. Other compositions are in powder form and include arsenic in the form of arsenious oxide. Each of these known termiticides must come into direct contact with a termite in order to kill the termite. However, termite nests are complex structures which include chambers linked by a complex system of tunnels. This means that it is very difficult and in practice virtually impossible to be able to deliver liquid or powdered agents to all parts of a termite nest. Further, not all termites access all parts of a nest. For example, workers do not enter the egg chambers. Thus, it is not possible to rely on termiticidal agents to be distributed to all areas of the nest by the termites themselves. The result of these difficulties is that under normal situations and using known agents it is not possible for all termites in a nest to be killed at one time. A termite nest can remain viable if only the queen and eggs survive, in which case a new colony can quickly breed. Thus in order to effectively kill a termite nest, repeat applications of the above known termiticides are required.
Other methods of termite control include providing a trap in which is housed an attractant and a poison. However, only those termites caught by the trap are killed and this method of control is not effective in killing an entire termite nest.
Insect and termite control by fumigation with active gaseous agents is also known. Whilst these methods of control may be able to expose more termites in a nest to the active agent as opposed to liquid spraying or dusting, fumigation has a number of disadvantages. First, fumigation is hazardous to the operator and also requires temporary evacuation of the site by personnel and domestic animals. Further, during fumigation, it is difficult to localize the active agent and prevent it from spreading into the environment.
An alternative to direct fumigation has been proposed for nematode control. Nematodes are parasitic worms which feed on plant roots. In this method, an aqueous thiocarbonate solution is sprayed onto or into nematode infected soil. Thiocarbonates are highly unstable and readily decompose on exposure to the soil to produce carbon disulfide. A disadvantage of these compounds is their instability and it is difficult to formulate storage stable solutions. These unstable thiocarbonates may be suitable for control of sedentary pests such as nematodes. However, such unstable compositions would be quite ineffective in the control of termites which are highly mobile and can travel large distances. The active agent would not remain viable in the environment for a sufficient period of time to allow any significant proportion of termites to com into contact with it.